Fmr. Bush aide: Trump's campaign 'on life support'

Donald Trump's last three days have been nothing short of a political nightmare, a former George W. Bush senior aide said.

"I thought that what Donald Trump did last night in the debate was he stemmed the bleeding, but he didn't ultimately get himself out of ICU," Sara Fagen told CNBC's "Squawk on the Street" on Monday.

Fagen went on to say that Trump's campaign "is on life support," and that with members of the Republican party abandoning their nominee, it will be difficult for him to turn the tides in his favor.

"I think the challenge for a lot of voters right now is they understand that what he really needs is a change of heart, and it's very difficult to manufacture that," she said.

Still, it is dangerous for Democrats to completely write off the Republican candidate, Democratic strategist Morris Reid said.

In the same interview, Reid, the former aide to the commerce secretary under Bill Clinton, said Trump has proven time and again to be unpredictably successful despite his digressions, which poses a challenge to Hillary Clinton.

"This will be an extremely close race because Donald Trump's voters are passionate," Reid said. "We need to make sure on the Democratic side that we're connecting with our voters, getting them out to vote, and … hopefully we'll win in November."

Reid said Clinton fared well in Sunday's debate, taking a measured approach and treating the race appropriately, as "a marathon, not a sprint."

The strategist said that Clinton succeeded in stabilizing her position and must now pivot to expanding her base of supporters, especially in battleground states.

He said the core voting block that will separate her from Trump will be educated white voters, with whom she is reportedly picking up momentum.